(x 3z×2y)^2-3y的值
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/29 13:15:43
后面那个x-y分之2{x+y}-3{x+y}分之x-y是怎么回事,能清楚一点吗前一个化简得x=-3y;后一个得(-4y/-4y)-4y/6y=1-2/3=1/3
(2x-y)(2x+y)+(2x-y)(y-4x)+2y(y-3x)=4x^2-y^2+2xy-8x^2-y^2+4xy+2y^2-6xy=-4x^2=-4(-1/4)^2=-1/4
(2x-y)/(x+y)=3所以(x+y)/(2x-y)=1/3原式=1/2*(2x-y)/(x+y)+1/3*(x+y)/(2x-y)=3/2+1/9=29/18
y的三次方-3y平方+y-2=y(y的平方-y-1)-2(y的平方-y-1)-4=-4
∵2x-y/x+2y=3∴2(2x-y)/x+2y-9(x+2y)/2x-y+3=2×3-9×1/3+3=6
答案是2.4x-2y/x+3y=(2x-y/x+3y)乘以2=4,4x+12y/2x-y=(x+3y/2x-y)乘以4=1/2x4=2,所以代数式等于4-2=2.
x+y分之x-y=2求x+y分之3x-3y减x-y分之2(x+y)的值x+y分之x-y=2x-y=2(x+y)(x+y)分之(3x-3y)-(x-y)分之2(x+y)的值x+y分之3x-3y=(x+y
x+y分之x-y=2x-y=2(x+y)求x+y分之3x-3y=(x+y)分之3(x-y)=(x+y)分之6(x-y)=6-x-y分之2(x+y)=-(x+y)分之2(x+y)=-2
∵(2y+3)(3y+2)-6y(y+3)+5y+16=6y2+4y+9y+6-6y2-18y+5y+16=22∴(2y+3)(3y+2)-6y(y+3)+5y+16的值与y的值无关.
y^3+5-12y^2+2-3y^2-2分之1y^3-y^2=-1+5-12+2-3+0.5-1=-9.53x-2x^2+5+3x^2-2x-5=3-2+5+3-2-5=2再问:能写的详细一些吗?再答
(x+y)(x-y)-y^2+(x-y)^2-(6x^2y-2xy^2)/(2y)=X^2-y^2-y^2+X^2+y^2-2xy-3x^2+xy=-x^2-y^2-xy=-(x^2+y^2+xy-3
x-y=3(x-y)^2=9x^2-2xy+y^2=9x^2+y^2=13(x+y)(x-y)-y^2-(6x^2y-2xy^2)/2y=x^2-y^2-y^2-3x^2+xy=-2(x^2+y^2)
若x-y/x+y=5则x-y=5(x+y)所以求x-y/2x+2y+5x+5y/3x-3y=5(x+y)/[2(x+y)]+5(x+y)/3(x-y)=5/2+5(x+y)/[3*5(x+y)]=5/
7y(x-3y)²-2(3y-x)³=7y(x-3y)²+2(x-3y)³=(x-3y)²[7y+2(x-3y)=(x-3y)²(7y+2X
先化简原式=(2X-Y)(2X+Y)+(2X-Y)(Y-4X)+2Y(Y-3X)=4x"2-y"2-8x"2-y"2+6xy+2y"2-6xy=-4x"2=-1/4可以确定上式得值
2乘以2+3分之一乘以二分之一=4+6分之1=6分之25
答案1/122---y^4/(y^8+3y^4+1)=1/(y^4+3+1/y^4)=1/[(y^2-1/y^2)^2+5]=1/[(y+1/y)^2(y-1/y)^2+5]----y^2+3y-1=
原式=(x+y)(x-y-x+2y)/y=(x+y)y/y=x+y因为已知代数式无意义,即:0的0次方无意义,所以3x-2y-7=0及2x+3y+4=0,解得:x=1,y=-2代入x+y=-1
你这个题目应该有地方弄错了吧,后面那个-2y*1/y不就直接是-2了.再问:题目没有错再答:7/3*√(9y)-y-2y*(1/y)=-27/3*√(9y)-y-2=-27/3*√(9y)-y=07/